Cement-pipe-stamping machine.



W L. VELTEN.

CEMENT PIPE STAMPING MACHINE.

APPLICATION FILED AUG. 28, 1911.

' Patented Apr. 23, 1912.

COLUMBIA PLANOGRAPH cO..wAsmNoToN. D. c.

W. LOTHAR VELTEN, OF WEIL-IM-DORF, NEAR STUTTGART, GERMANY.

CEMENT-PIPE-STAMPING MACHINE.

Specification of Letters Patent.

Application filed August 28, 1911.

Patented Apr. 23, 1912.

Serial No. 646,352.

To all whom it may concern:

Be it known that I, W. LOTHAR VELTEN, a subject of the King of IVurt-temberg, and residing at l/Veil-im-Dorf, near Stuttgart, in the Kingdom of VVurttemberg, and in the German Empire, have invented certain new and useful Improvements in Cement-Pipe- Stamping Machines, of which the following is a specification.

It is known, to make cement pipes by means of a stamping member axially slidable and rotatable within a hollow mold, in such a manner that the stamping member is lifted together with the core connected to it and is then rotated without the core and subsequently dropped, so that the material delivered underneath the stamping member at the lifting of the latter is then stamped. In said known stamping machines the material to be stamped is delivered underneath the stamping member either thereby that it passes downwardly between the segment shaped attachment pieces arranged at the periphery of the stamping member or thereby that it passes downwardly between the upper end of the core and the lower end of the stamping member. The exterior shape of pipes made by said known machines is not perfectly circular as compared with the passage opening and the thinner portions of the walls of said pipes are leaky, especially in pipes of larger diameters. This is due to the fact, that at those points of the hollow mold, which extend beyond the circle of the stamping attachments, considerably more material to be stamped drops downwardly, when the stamping member is lifted, than at those points, at which the hollow mold tightly incloses the stamping attachments. Accordingly the stamping operation progresses so rapidly at the first named points, that at the other points the material cannot be stamped sufficiently tight with the result that the pipes made by said known machines are not suited for practical use. In said known stamping machines the friction resulting from the stamping causes the upper portion of the core to become thinner than the lower portion, as said lower portion is less subjected to friction than the upper part. If a core, which has acquired a conical shape in this manner, shall be lifted out of the pipe, the top end of the pipe, especially its inner edge will be damaged, no matter how strongly the upper portion of the pipe has been stamped; the cause of this is, that,

when the core is lifted, the lower portion of the same must be drawn through an opening having a smaller diameter than the core itself. It is therefore always necessary to repair the top end of the pipe. F urtherstamping machines are known, in which the material to be stamped is pressed into the form of a pipe by means of a screw shaped attachment piece, arranged at the periphery of a rotating core.

The subject matter of the application differentiates from the known machines therein, that not the core or the hollow mold or the core in connection with the stamping member, but the latter itself is constructed as receptacle for the material to be stamped. From this receptacle the material passes beneath the stamping face through openings provided in the stamping member and extending in the direction of the rotation and of the stroke of the latter, the material to be stamped, when being discharged from the receptacle not coming into contact with either the core or the hollow mold and not being jammed within the openings by the ro tating movement of the stamping member. The result of this is, that neither the operation nor the product is impaired by the friction of the material and that the latter always passes underneath the stamping member in the same quantity and independently of the exterior shape of the pipe to be made. Furthermore the core project-s into the hollow mold and into the stamping member from below and is drawn out from the cement pipe downwardly and not upwardly, which can be done very easily and without any damaging of the cement pipe in contrast to the known machines.

In the drawing in which two forms of construction of the subject matter of the application are shown, Figure 1 is a vertical section through the stamping machine, the stamping member being partly shown in elevation. Fig. 2 is a plan view-0f Fig. 1. Fig. 3 is a detail section of the stamping member. Fig. 4 is a detail section of a modified form of the stamping member and Fig. 5 is a diagrammatical view'of the machine.

a indicates a two part hollow mold preferably constructed of sheet metal and corresponding in cross section to the outside shape of a cylindrical pipe with longitudinally extending broad base. Into the base portion of the mold, the lower end of which rests on a supporting member, a ring 6 is removably inserted, the bore of which is perfectly circular and which serves as mold piece for one end of the pipe to be made. In the bore of the ring a vertically slidable pipe 0 is arranged, which serves as a core for the pipe to be made. A stamping mem ber (Z, the upper part of which is constructed as receptacle for the material to be stamped, while its lower part is formed in a known manner as a bell and closely fits upon the upper end ,of the core, is rotatably and slidably arranged upon said core and is rigidly attached to the lower end of a vertical shaft 6, which can be lifted and simultaneously rotated in the direction indicated by the arrow in Fig. 1 and finally vertically dropped by a gearing not shown in the drawings. The lower end of the core 0 removably rests upon a horizontal support 2', the ends of which are secured to vertical rack-hars 71:. Each of the latter is provided at its upper end with a laterally projecting pin Z, with the underside of which a pawl m may engage. The pawls m are arranged at the ends of a transverse bar a, to which the rack bars Z: are usually thereby connected,

'that the pawls m engage under the pins Z.

The pawls m are formed in such a manner, that they are held in operative position by their own weight. The transverse bar a is slidably guided longitudinally of the two rack bars so that, after being disconnected from the rack bars by disengagement of the pawl m with the pins Z it cannot rotate relatively thereto. To the transverse bar it a sliding ring p is secured and below said ring a spider 0 is mounted on the shaft, each of the ends of the arms of said spider carrying a roller 0. When the stamping member or the shaft 6 respectively are lifted said rollers strike from below against the sliding ring 79 and upon the rotation of the shaft roll on the underside of said sliding ring. This operation causes a lifting of the transverse bar a and thereby of the rack bars Z6 and of the core 0 respectively. For purpose of preventing the lowering of the rack bars 75 at the time that the shaft 6 is lowered, pawls q are provided, which automatically engage with the racks of the rack-bars 72. For the purpose of simultaneously disengaging both pawls from the rack bars, the former are connected with each other by means of levers r and a sliding rod S, which can be reciprocated horizontally by means of a lever 25. To permit the core 0 to be lowered slowly and to prevent its dropping downwardly by gravity, after the pawls 9 have been disengaged, two gear wheels u are in mesh with the rack bars 70, and said gear wheels can be rotated or retarded respectively by a crank, regulating device, etc.

The lower end of the stamping member is provided with an annular projection (Z' corresponding to a central groove of the ring 6.

From the receptacle of the stamping member a plurality of passages 7, extending in the direction of the rotative and stroke motion of the stamping member lead to the stamping faces. The rearwardly and downwardly inclined position of these passages f, with respect to the direction of rotation of the stamping member, serves the purpose that the material to be stamped and contained in said passages or already discharged from the latter cannot either be pressed into these passages, nor can be jammed within the same, when the stamp ing member is rotated, but is free to drop downwardly without being retarded.

In the form of construction of the stamping member shown in Figs. 1-3 the edges of the passages f, which are the rearmost in regard to the direction of rotation of the stamping member, are lined by wiping bars 9 removably mounted in the outer casing of the stamping member and bearing against the interior walls of the hollow mold, said. wiping bars preventing that at the rotation of the stamping member the material to be stamped can be discharged laterally from the passages f and further preventing, that said material can pass be tween the exterior walls of the stamping member and the interior walls of the hollow mold. When the wiping edges of the bars g are worn off, said bars can be replaced by new ones. For the purpose of avoiding that material to be stamped may pass from above to the space between the stamping member and the hollow mold and may cause friction there, the stamping member at the upper edge of its periphery is adapted to the circular portion of the hollow mold, while the lower port-ion of the stamping member does not closely bear against the inner wall of the hollow mold, so that, in case some of the material. to be stamped should pass into the space between the periphery of the stamping member and the inner wall of the hollow mold, said material. can drop downwardly without causing any material friction.

In the modified form of the stamping member, illustrated in Fig. 4, the passages f of said stamping member are closed laterally by a bent plate 72 countersunk into the stamping member, so that the passages f are open only at their upper and lower ends.

The operation of the described pipe stamping machine is as follows: The cement to be stamped to the form of a pipe is fed into the receptacle of the stamping member, serving to receive said cement. Thereupon the shaft 6 or the stamping member respectively is raised and the latter is simultane ously rotated in the direction indicated by the arrow in Fig. 1, so that the cement contained in and above the passages f drops downwardly through said passages and is delivered beneath the stamping face of the stamping member (Z, where it is compressed by the sudden downward movement of the stamping member. According to the progress made in forming the pipe the core 0 is moved upwardly; at each upward movement of the stamping member, the core is raised for a distance which corresponds to the height of the immediately before stamped layer, while at the upward movement of the stamping member the core remains in a fixed position, being held on its level, to which it had been raised by the roller 0 by means of the pawls g in connection with the rack bars 70. The described operation is repeated until a pipe has been finished. Thereupon the pawls m are disengaged, the stamping member is lifted and the core 0 is lowered in the manner already described, or is drawn out of the cement pipe in a downward direction, then after removing the cement pipe the hollow form is replaced, the stamping member is lowered and the pawls m are brought again in en-- gagement, so that a new pipe can be made.

According to the present invention the stamping member is constructed in such a manner, that the material to be stamped cannot cause any friction either between the core and the stamping member or between the stamping member and the hollow mold. The result of this construction is, that the lifting of the stamping member is not rendered ditficult by friction of the material to be stamped and that the effect of the fall of the stamping member is not diminished.

Having thus particularly described my invent-ion what I claim as new and desire to secure by Letters Patent is 1. In a cement pipe stamping machine a vertically movable and rotatable stamping member placed upon an axially. slidable core, said core projecting into a hollow mold and being adapted to be downwardly withdrawn from said mold, a receptacle for the material to be stamped, formed in the upper end of said stamping member and inclined passages in the stamping member, leading downwardly to the stamping face of the stamping member and extending in a direction opposite to the direction of rotation of said stamping member.

2. In a cement pipe stamping machine a vertically movable and rotatable stamping member, an axially slidable core, a hollow mold, a receptacle for the material to be stamped formed in the upper part of the stamping member, passages in said stamping member serving to convey the material to be stamped to the stamping face of said stamping member, and wiping bars provided at those edges of the outlet openings of said passages, which are the rearmost in regard to the direction of rotation of said stamping member, said wiping bars preventing that at the rotation of the stamping member the material to be stamped can pass between the outer wall of the stamping member and the inner wall of the hollow mold.

In testimony whereof I affix my signature in presence of two witnesses.

W. LOTHAR VELTEN. -Witnesses:

ERNEST ENTENMANN, FRIDA KLAITER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

